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Northwest Arkansas via Chicago Area via Straight Up from There on Lake Superior

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VisionPro IAQ Tstat versus 2-Stage Compressor/VS Furnace

I have a new York 2-stage YZH DFHP with VS, modulating furnace and a Honeywell VisionPro IAQ tstat with a remote EIM at the furnace.

The contractor asked me how I want the tstat set up. Haven't a very good idea on that. Not sure he does either since he hasn't installed an IAQ tstat before. The IAQ install manual seems to pretty much list a bunch of options and the choices. Doesn't spend a lot of time giving an overview of the whole process and interactions.

As background, the York diagram in the install manual for a VS or PSC modulating furnace with 2-stage HP says to set up the York tstat to be 3 Heat/2 Heat Pump (don't know what tstat that is but mentions options that sound like an IAQ derivative).

The contractor initially turned on the AC for a few days with no furnace yet and without much programming. After the initial hours where the DFHP caught up with the 90+ temps in the house due to no installed system, it has basically been running at low blower and stage 1 HP - been cooler since install. It did seem initially that it short cycled in less than 5 minutes but seems to be running much longer now once in a while. Also seems to be dehumidifying to the 50% humidity level that is set. I think this thing is too smart for me even without full programming.

The IAQ has a lot of "E", for "Auto Discover", option choices. Is that a reliable way to set up the IAQ tstat so it can figure out the best way to control the HP and the VS furnace?

Northwest Arkansas via Chicago Area via Straight Up from There on Lake Superior

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Better IAQ Manual

Did a Google search and came up with a much more informative manual written in 2006 for an IAQ with EIM. It is not as abbreviated as those that shipped with my unit. No multiple language stuff, all English. It covers the whole spectrum of wiring, placement, etc. The biggy for me is that the option definitions are better with interactions between different options. And it covers recommended cycles per hour. But maybe not good enough for the HVAC non-wannabe.

Understand the 2 stages of cooling but still don't understand what the 3 stages of heat are that York recommends. Thought that it might mean compressor stage 1, compressor stage 2 and backup NG VS modulating furnace. But haven't found any explanation that confirms this. Any ideas?